US20120218032A1 - High efficiency negative regulated charge-pump - Google Patents

High efficiency negative regulated charge-pump Download PDF

Info

Publication number
US20120218032A1
US20120218032A1 US13/105,012 US201113105012A US2012218032A1 US 20120218032 A1 US20120218032 A1 US 20120218032A1 US 201113105012 A US201113105012 A US 201113105012A US 2012218032 A1 US2012218032 A1 US 2012218032A1
Authority
US
United States
Prior art keywords
output
electronic switch
voltage
charge
coupled
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
US13/105,012
Other versions
US8461910B2 (en
Inventor
Praveen Varma Nadimpalli
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Qorvo US Inc
Original Assignee
RF Micro Devices Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by RF Micro Devices Inc filed Critical RF Micro Devices Inc
Priority to US13/105,012 priority Critical patent/US8461910B2/en
Assigned to RF MICRO DEVICES, INC. reassignment RF MICRO DEVICES, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: NADIMPALLI, PRAVEEN VARMA
Publication of US20120218032A1 publication Critical patent/US20120218032A1/en
Assigned to BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT reassignment BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT NOTICE OF GRANT OF SECURITY INTEREST IN PATENTS Assignors: RF MICRO DEVICES, INC.
Application granted granted Critical
Publication of US8461910B2 publication Critical patent/US8461910B2/en
Assigned to RF MICRO DEVICES, INC. reassignment RF MICRO DEVICES, INC. TERMINATION AND RELEASE OF SECURITY INTEREST IN PATENTS (RECORDED 3/19/13 AT REEL/FRAME 030045/0831) Assignors: BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT
Assigned to QORVO US, INC. reassignment QORVO US, INC. MERGER (SEE DOCUMENT FOR DETAILS). Assignors: RF MICRO DEVICES, INC.
Expired - Fee Related legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
    • H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
    • H02M3/06—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using resistors or capacitors, e.g. potential divider
    • H02M3/07—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using resistors or capacitors, e.g. potential divider using capacitors charged and discharged alternately by semiconductor devices with control electrode, e.g. charge pumps
    • H02M3/073—Charge pumps of the Schenkel-type
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
    • H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
    • H02M3/06—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using resistors or capacitors, e.g. potential divider
    • H02M3/07—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using resistors or capacitors, e.g. potential divider using capacitors charged and discharged alternately by semiconductor devices with control electrode, e.g. charge pumps
    • H02M3/071—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using resistors or capacitors, e.g. potential divider using capacitors charged and discharged alternately by semiconductor devices with control electrode, e.g. charge pumps adapted to generate a negative voltage output from a positive voltage source

Definitions

  • the present disclosure relates to charge-pumps that provide regulated negative voltages.
  • negative voltage charge-pumps are used to control radio frequency (RF) switches that are implemented using a pseudomorphic high electron mobility transistor/complementary metal oxide semiconductor (pHEMT/CMOS) process.
  • Negative voltage generated by a negative voltage charge-pump is usable to turn off pHEMT/CMOS based RF switches.
  • Using a negative voltage instead of a positive voltage improves the isolation of a pHEMT/CMOS based RF switch and eliminates the need for DC blocking capacitors for proper operation of pHEMT/CMOS based RF switches.
  • the lack of blocking capacitors reduces the area needed to implement a pHEMT/CMOS based RF switch, which simplifies the design of electrostatic discharge (ESD) protection.
  • ESD electrostatic discharge
  • RF switches driven by a negative charge-pump typically have leakage currents that are supplied through a negative voltage output of the negative charge-pump. If an unregulated negative charge-pump is used to supply the leakage currents, an output voltage provided at the negative voltage output drops as the leakage currents increase. As a result, insertion losses and isolation numbers for the RF switches are adversely affected. In contrast, a regulated negative charge-pump will maintain a fixed output voltage as the leakage currents increase. It has been recognized that improved efficiencies can be realized by sourcing load currents in a feedback loop of the regulated negative charge-pump directly from a main power supply. For example, twice as much current will be drained from the main power supply if a load current is sourced from a voltage doubled section of the feedback loop. Such a large drain of current from the main power supply is inefficient and undesirable.
  • a regulated negative charge-pump will operate most efficiently when voltage regulation of the output voltage of the regulated negative charge-pump is maintained near to the regulated negative charge-pump's ideal output voltage. For example, an ideal output voltage for a regulated negative charge-pump that doubles a source voltage is twice the voltage of the source voltage.
  • a regulated negative charge-pump that is designed to boost a source voltage V dd by a multiplication factor N will operate most efficiently when a negative output voltage V OUT is maintained at N times the source voltage V dd .
  • Efficiency for a charge-pump is given by the following equation:
  • FIG. 1 depicts a related art shunt regulated negative charge-pump 10 having a flying capacitor stage 12 with a capacitor C FLY having a first terminal that is selectively coupled between a first negative voltage source 14 through a first electronic switch 51 and a negative voltage output 16 through a second electronic switch S 2 .
  • the capacitor C FLY also has a second terminal that is coupled to a fixed voltage node such as ground GND.
  • the first electronic switch S 1 is driven by a clock signal CLK
  • the second electronic switch S 2 is driven by a clock signal CLK .
  • a positive regulated voltage source 18 is communicatively coupled to the negative voltage output 16 through a feedback network 20 made up of a first resistor R 1 and a second resistor R 2 coupled in a voltage divider configuration.
  • An error amplifier 22 has an inverting input 24 coupled to a voltage divider node 26 between the first resistor R 1 and the second resistor R 2 .
  • the error amplifier 22 further includes a non-inverting input 28 that is coupled to a negative voltage reference ⁇ V REF .
  • the error amplifier 22 is powered by a second negative voltage source 32 that provides a negative supply voltage that is above the negative output voltage V OUT , and a third negative voltage source 34 that provides a negative voltage that is below the negative output voltage V OUT .
  • a voltage of ⁇ 3V dd for the first negative voltage source 14 and the third negative voltage source 34 is generated by a negative voltage quadrupler (not shown).
  • a voltage of ⁇ 2V dd for the second negative voltage source 32 is generated by a negative voltage tripler (not shown).
  • the negative voltage tripler is able to triple the source voltage V dd because a voltage equal to ⁇ V dd is generated by a voltage doubler circuit (not shown) that is sourced from V dd .
  • a cascading of two voltage doubler circuits can be adapted to provide a voltage tripler circuit.
  • the shunt regulated negative charge-pump 10 also includes an n-channel enhancement mode FET M 1 that has a gate coupled to an error signal output 30 of the error amplifier 22 .
  • the FET M 1 also has a source coupled to the third negative voltage source 34 , and a drain coupled to the negative voltage output 16 .
  • a load capacitor C LOAD has a first terminal coupled to the negative voltage output 16 , and a second terminal coupled to a fixed voltage node such as ground GND.
  • the flying capacitor C FLY is charged to ⁇ 3V dd .
  • the FET M 1 turns on and pulls charge away from the capacitor C FLY and the capacitor C LOAD until a voltage at the voltage divider node 26 is equal to the reference voltage ⁇ V REF .
  • the load current I LOAD comes from the second negative voltage source 32 , which in this case supplies a voltage of ⁇ 2V dd .
  • the second negative voltage source 32 supplying the load current I LOAD at a voltage of ⁇ 2V dd , the source of the voltage V dd must supply three times as much current as the load current I LOAD .
  • the efficiency of the shunt regulated negative charge-pump 10 is less than the efficiency desired for battery powered equipment such as mobile terminals.
  • FIG. 2 depicts a related art series regulated negative charge-pump 36 that is similar to the shunt regulated negative charge-pump 10 ( FIG. 1 ).
  • the FET M 1 is a p-channel enhancement mode type device that has a drain coupled directly to the second negative voltage source 32 .
  • the FET M 1 has a source coupled to the negative voltage output 16 .
  • the source of the FET M 1 is also coupled to the third negative voltage source 34 through a third resistor R 3 .
  • the load current I LOAD is still supplied by the second negative voltage source 32 , which in this case supplies a voltage of ⁇ 2V dd .
  • the second negative voltage source 32 supplies the load current I LOAD at a voltage of ⁇ 2V dd .
  • the source of the voltage V dd must supply three times as much current as the load current I LOAD .
  • the series regulated negative charge-pump 36 also provides less than the efficiency desired for battery powered equipment such as mobile terminals. Therefore, a need remains for a high efficiency regulated negative charge-pump.
  • the present disclosure provides a high efficiency negative regulated charge-pump, which in certain embodiments is implemented via a Silicon-on-insulator (SOI) process or a Deep negative-well (N-Well) complementary metal oxide semiconductor (CMOS) process.
  • SOI Silicon-on-insulator
  • N-Well Deep negative-well
  • CMOS complementary metal oxide semiconductor
  • the present disclosure provides a circuit that includes at least one flying capacitor stage with a capacitor having a first terminal that is selectively coupled to either a negative voltage input through a first electronic switch or a negative voltage output through a second electronic switch.
  • the capacitor also has a second terminal that is selectively coupled between a fixed voltage node through a third electronic switch and an error signal input through a fourth electronic switch.
  • the circuit also has a positive voltage source that is communicably coupled to the negative voltage output through a feedback network having a feedback output.
  • a feedback amplifier having an error signal output, a reference voltage input, and a feedback input coupled to the feedback output of the feedback network.
  • the error signal output of the feedback amplifier is coupled to the error signal input.
  • a switch controller has a first clock output for driving the first electronic switch and the third electronic switch, and a second clock output for driving the second electronic switch and the fourth electronic switch.
  • FIG. 1 depicts a related art shunt regulated negative charge-pump.
  • FIG. 2 depicts a related art series regulated negative charge-pump.
  • FIG. 3 depicts a high efficiency regulated negative charge-pump that is in accordance with the present disclosure.
  • FIG. 4 depicts a regulated negative charge-pump that is driven by a negative voltage doubler having two stages in accordance with the present disclosure.
  • FIG. 5 depicts a regulated negative charge-pump having a plurality of stages that are driven by a feedback amplifier that is in accordance with the present disclosure.
  • FIG. 6 depicts a detailed circuit implementation of the high efficiency regulated negative charge-pump of the present disclosure.
  • FIG. 7 depicts a deep trench negative metal oxide semiconductor (NMOS) device structure that is suitable for implementing the NMOS devices depicted in FIG. 6 .
  • NMOS deep trench negative metal oxide semiconductor
  • FIG. 8 depicts a deep trench positive metal oxide semiconductor (PMOS) device structure that is suitable for implementing the PMOS devices depicted in FIG. 6 .
  • PMOS deep trench positive metal oxide semiconductor
  • FIG. 9 depicts a deep N-Well NMOS structure that is suitable for implementing the NMOS devices depicted in FIG. 6 .
  • FIG. 10 is a graph depicting output voltage measurements for a realized circuit based upon the circuit depicted in FIG. 6 .
  • FIG. 11 depicts user equipment (UE) in the form of a mobile terminal that incorporates a preferred embodiment of the circuit of FIG. 6 .
  • UE user equipment
  • FIG. 3 depicts a high efficiency regulated negative charge-pump 38 that is in accordance with the present disclosure.
  • the high efficiency regulated negative charge-pump 38 includes a flying capacitor stage 40 with a capacitor C FLY having a first terminal that is selectively coupled to either a negative voltage source 42 through a first electronic switch S 1 or a negative voltage output 44 through a second electronic switch S 2 .
  • the capacitor C FLY also has a second terminal that is selectively coupled to a fixed voltage node such as ground GND through a third electronic switch S 3 .
  • the second terminal of the capacitor C FLY is also selectively coupled through a fourth electronic switch S 4 to an error signal input 48 .
  • a positive voltage source 50 is communicably coupled to the negative voltage output 44 through a feedback network 52 made up of a first resistor R 1 and a second resistor R 2 coupled in a voltage divider configuration.
  • a feedback amplifier 54 has an inverting input 56 coupled to a feedback output at a voltage divider node 58 between the first resistor R 1 and the second resistor R 2 .
  • the feedback amplifier 54 also includes a non-inverting input 60 that is coupled to a positive voltage reference +V REF .
  • the feedback amplifier 54 further includes an output 62 that is coupled to the error signal input 48 .
  • the feedback amplifier 54 may be powered directly from V dd and a fixed voltage node, which in this case is ground GND. Therefore, a load current I LOAD is directly supplied from V dd .
  • I LOAD being directly supplied by V dd
  • the high efficiency regulated negative charge-pump 38 is at least three times as efficient as either the regulated negative charge-pump 10 or the regulated negative charge-pump 36 .
  • the electronic switches S 1 and S 3 are closed in response to a first state of the first clock signal CLK, while the switches S 2 and S 4 are opened in response to a first state of the second clock signal CLK . While the electronic switches S 1 and S 3 are closed, the capacitor C FLY is charged to a voltage level of ⁇ 3V dd . Once the capacitor C FLY is charged, the electronic switches S 1 and S 3 are opened in response to a second state of the first clock signal CLK. After a short delay that prevents an overlap of the first clock signal CLK and the second clock signal CLK , the electronic switches S 2 and S 4 are closed in response to a second state of the second clock signal CLK .
  • the output 62 of the feedback amplifier 54 provides an output voltage level that adds or subtracts from the voltage of the charged capacitor C FLY depending upon a comparison of the reference voltage +V REF and the feedback output at a voltage level present at the voltage divider node 58 .
  • the output 62 will pull charges from the capacitor C FLY and the capacitor C LOAD .
  • the output 62 will add charge to the capacitor C FLY and the capacitor C LOAD . In this way, a negative voltage level I OUT provided at the negative voltage output 44 is regulated.
  • FIG. 4 depicts another regulated negative charge-pump 64 that is in accordance with the present disclosure.
  • the regulated negative charge-pump 64 has a first stage 66 and a second stage 68 that are driven by a negative voltage doubler circuit 70 .
  • the first stage 66 includes a flying capacitor C FLY1 having a first terminal coupled to a first electronic switch S 11 and a second electronic switch S 21 .
  • the flying capacitor C FLY1 also has a second terminal coupled to a third electronic switch S 31 and a fourth electronic switch S 41 .
  • the second stage 68 includes a flying capacitor C FLY2 having a first terminal coupled to a first electronic switch S 12 and a second electronic switch S 22 .
  • the flying capacitor C FLY2 also has a second terminal coupled to a third electronic switch S 32 and a fourth electronic switch S 42 .
  • the first terminal of the flying capacitor C FLY1 is selectively coupled to the negative voltage doubler 70 via the first electronic switch S 11 , while the second terminal of the flying capacitor C FLY2 is selectively coupled to a fixed voltage node such as ground GND.
  • the first terminal of the flying capacitor C FLY1 is also selectively coupled to the first terminal of the flying capacitor C FLY2 via the second electronic switch S 21 of the first stage 66 and the first electronic switch S 12 of the second stage 68 , wherein the first electronic switch S 12 and the second electronic switch S 21 are both driven by the second clock signal CLK .
  • the first terminal of the flying capacitor C FLY2 is also selectively coupled to the negative voltage output 44 through the second electronic switch S 22 .
  • the second terminal of the flying capacitor C FLY2 is selectively coupled to the second terminal of the flying capacitor C FLY1 via the third electronic switch S 32 and the third electronic switch S 41 .
  • the second terminal of the flying capacitor C FLY2 is selectively coupled to the output 62 of the feedback amplifier 54 through the fourth electronic switch S 42 .
  • the electronic switches S 11 and S 31 are closed in response to a first state of the first clock signal CLK, while the electronic switches S 21 , S 41 , S 12 , and S 32 are opened in response to a first state of the second clock signal CLK . While the electronic switches S 11 and S 31 are closed, the capacitor C FLY1 is charged to a voltage level of around ⁇ 3V dd . Once the capacitor C FLY1 is charged, the electronic switches S 11 and S 31 are opened in response to a second state of the first clock signal CLK. After a short delay that prevents an overlap of the first clock signal CLK and the second clock signal CLK , the electronic switches S 21 , S 41 , S 12 and S 32 are closed in response to a second state of the second clock signal CLK .
  • the output 62 of the feedback amplifier 54 provides an output voltage level that adds or subtracts from the voltage of the capacitors C FLY1 and C FLY2 depending upon a comparison of the reference voltage +V REF and the feedback output at a voltage level present at the voltage divider node 58 .
  • the output 62 will pull charge from the capacitors C FLY1 and C FLY2 .
  • the output 62 will add charge to the capacitors C FLY1 and C FLY2 .
  • the first clock signal CLK and the second clock signal CLK both change state so that the electronic switches 521 , 541 , S 12 and S 32 are opened, while the electronic switches S 11 , 531 , S 22 and S 42 are closed.
  • the charge is transferred from the capacitor C FLY2 to the capacitor C LOAD
  • the feedback amplifier 54 provides an output voltage level that adds or subtracts from the voltage of the capacitors C FLY1 and C FLY2 depending upon a comparison of the reference voltage +V REF and the feedback output at a voltage level present at the voltage divider node 58 .
  • a negative voltage level V OUT provided at the negative voltage output 44 , is regulated.
  • the capacitor C FLY1 is being recharged as charge is being transferred from C FLY2 to C LOAD .
  • FIG. 5 depicts a regulated negative charge-pump 72 that extends the two stage embodiment of the regulated negative charge pump 64 ( FIG. 4 ) to include additional flying capacitor stages in accordance with the present disclosure.
  • (N+1) stages are added to the first stage 66 , where (N+1) is a total number of flying capacitor stages included in the regulated negative charge-pump 72 .
  • the first terminal of the first flying capacitor C FLY1 is selectively coupled to a fixed voltage node such as ground GND through the first first-stage electronic switch S 11 .
  • the second terminal is selectively coupled to the voltage source V dd , through the fourth first-stage electronic switch S 41 .
  • a stage N 74 includes a flying capacitor C FLYN having a first terminal coupled to a first electronic switch S 4 N and a second electronic switch S 2 N.
  • the flying capacitor C FLYN also has a second terminal coupled to a third electronic switch S 3 N and a fourth electronic switch S 4 N.
  • the first terminal of C FLYN is selectively coupled to a previous stage through the first electronic switch S 1 N. For example, if the total number of stages (N+1) equals three, then the first electronic switch S 1 N will be coupled to the electronic switch S 21 of the first stage 66 .
  • a second terminal of the flying capacitor C FLYN is selectively coupled to the output 62 of the feedback amplifier 54 through the third electronic switch S 3 N.
  • a stage (N+1) 76 includes a flying capacitor C FLY(N+1) having a first terminal coupled to a first electronic switch S 1 (N+1) and a second electronic switch S 2 (N+1).
  • the flying capacitor C FLY(N+1) also has a second terminal coupled to a third electronic switch S 3 (N+1) and a fourth electronic switch S 4 (N+1).
  • the first terminal of the flying capacitor C FLY(N+1) is selectively coupled to a first terminal of the flying capacitor C FLYN of the stage N via the first electronic switch S 1 (N+1) and the second electronic switch S 2 N that are both driven by the first clock signal CLK.
  • the first terminal of the flying capacitor C FLY(N+1) is also selectively coupled to the negative voltage output 44 through the second electronic switch S 2 (N+1).
  • the second terminal of the flying capacitor C FLY(N+1) is selectively coupled to the second terminal of the flying capacitor C FLYN via the third electronic switch S 3 (N+1) and the third switch S 3 N.
  • the second terminal of the flying capacitor C FLY(N+1) is selectively coupled to the output 62 of the feedback amplifier 54 through the fourth electronic switch S 4 (N+1).
  • FIG. 6 depicts a detailed circuit implementation of a high efficiency regulated negative charge-pump 78 in accordance with the present disclosure.
  • a cross-coupled negative charge pump circuit 80 having a first P-FET MP 1 , a second P-FET MP 2 , a first N-FET MN 1 and a second N-FET MN 2 along with a first flying capacitor CF 1 , a second flying capacitor CF 2 and a first load capacitor CL 1 provides the high efficiency regulated negative charge-pump 78 with an input voltage of ⁇ V dd .
  • a first terminal of the first flying capacitor CF 1 is driven by a first clock signal CLK
  • a first terminal of the second flying capacitor CF 2 is driven by a second clock signal CLK .
  • the first clock signal CLK is opposite in phase to the second clock signal CLK , and in this case the amplitude of the first clock signal CLK and the amplitude of the second clock signal CLK are both about equal to V dd .
  • a switch controller 79 has a first clock output for providing the first clock signal CLK and a second clock output for providing the second clock signal CLK .
  • the switch controller 79 is depicted as an element of the regulated negative charge-pump 78 , the switch controller 79 could also be external of the regulated negative charge-pump 78 .
  • the high efficiency regulated negative charge-pump 78 includes a P-FET MP 3 , a P-FET MP 4 , an N-FET MN 3 , an NFET MN 4 , an NFET MN 5 and an NFET MN 6 .
  • the high efficiency regulated negative charge-pump 78 also includes flying capacitors CF 3 , CF 4 , CF 5 and CF 6 .
  • a load capacitor C LOAD is coupled between a negative voltage output 81 and a fixed voltage node such as ground GND.
  • a first terminal of the flying capacitor CF 3 is selectively coupled to the negative voltage output 81 through a first electronic switch SW 1 that is responsive to the second clock signal CLK .
  • a second terminal of the flying capacitor CF 3 is selectively coupled to ground GND through the NFET MN 5 having a gate that is responsive to the first clock signal CLK.
  • a first terminal of the flying capacitor CF 6 is selectively coupled to the negative voltage output 81 through a second electronic switch SW 2 that is responsive to the first clock signal CLK.
  • a second terminal of the flying capacitor CF 6 is selectively coupled to ground GND through the NFET MN 6 having a gate that is responsive to the second clock signal CLK .
  • the sources of PFET MP 3 and the PFET MP 4 receive the ⁇ V dd voltage provided by the cross-coupled negative charge pump circuit 80 .
  • the flying capacitor CF 4 is coupled between a drain of the PFET MP 3 and a gate of the NFET MN 6 , which is driven by the second clock signal CLK .
  • the flying capacitor CF 5 is coupled between a drain of the PFET MP 4 and a gate of the NFET MN 5 , which is driven by the first clock signal CLK.
  • the NFET MN 3 has a source coupled to a first terminal of the flying capacitor CF 3 that is coupled to the first electronic switch SW 1 .
  • a drain of the NFET MN 3 is coupled to a first terminal of the flying capacitor CF 4 and to a drain of the PFET MP 3 .
  • a gate of the NFET MN 3 is coupled to the gate of PFET MP 3 , which in turn is coupled to the drain of the PFET MP 4 and the source of NFET MN 4 .
  • the NFET MN 4 has a source coupled to a first terminal of the flying capacitor CF 5 that is coupled to the second electronic switch SW 2 .
  • a gate of the NFET MN 4 is coupled to the gate of PFET MP 4 , which in turn is coupled to the drain of the PFET MP 3 and the source of the NFET MN 3 .
  • a second terminal of the capacitor CF 4 is driven by the second clock signal CLK , which has an amplitude that alternates between around zero volts and around V dd .
  • the second terminal of the capacitor CF 5 is driven by the first clock signal CLK, which has an amplitude that alternates between around V dd and around zero volts.
  • Regulation of a negative output voltage V OUT at the negative voltage output 81 is maintained by a feedback amplifier 82 that has a non-inverting input 84 coupled to a positive voltage reference +V REF and an inverting input 86 coupled to a voltage feedback signal VFB that is a sample of the negative output voltage.
  • An output terminal 88 of the feedback amplifier 82 is selectively coupled to the second terminal of the flying capacitor CF 3 through an electronic switch SW 3 that is driven by the second clock signal CLK .
  • Another electronic switch SW 4 that is driven by the first clock signal CLK selectively couples an output voltage provided at the output terminal 88 of the feedback amplifier 82 to the second terminal of the flying capacitor CF 6 .
  • the flying capacitor CF 4 In operation, during a first charging phase when the first clock signal CLK is around +V dd and the second clock signal CLK is around zero volts, the flying capacitor CF 4 is charged to ⁇ V dd . As the second clock signal CLK transitions to an amplitude of around +V dd , the voltage across CF 4 is raised to around ⁇ 2V dd . During a first output regulation phase, as the first clock signal CLK transitions to around +V dd and the second clock signal CLK transitions low, the electronic switch SW 3 closes in response to the second clock signal CLK . As a result, an output voltage provided at the output terminal 88 adjusts the voltage across the flying capacitor CF 3 .
  • the output voltage provided at the output terminal 88 will add charge to the flying capacitor CF 3 .
  • the output voltage provided at the output terminal 88 will subtract charge from the flying capacitor CF 3 .
  • the flying capacitor CF 6 is charged to ⁇ V dd .
  • the voltage across CF 6 is raised to around ⁇ 2V dd .
  • the electronic switch SW 4 closes in response to the first clock signal CLK.
  • an output voltage provided at the output terminal 88 adjusts the voltage across the flying capacitor CF 6 . If the voltage level of the feedback signal VFB is less than the voltage level of the positive reference voltage +V REF , the output voltage provided at the output terminal 88 will add charge to the flying capacitor CF 6 . Alternately, if the voltage level of the feedback signal VFB is greater than the voltage level of the positive reference voltage +V REF , the output voltage provided at the output terminal 88 will subtract charge from the flying capacitor CF 6 .
  • the high efficiency regulated negative charge pump 78 can be converted to a high efficiency regulated positive charge pump by replacing the PMOS transistors with NMOS transistors and vice versa.
  • the negative voltage reference ⁇ V REF should also be replaced by a positive voltage reference +V REF .
  • the high efficiency regulated negative charge pump 78 is preferably fabricated such that the PFETs MP 1 , MP 2 , MP 3 and MP 4 are placed in a deep trench using an SOI process.
  • the reason for placing the PFETs MP 1 , MP 2 , MP 3 and MP 4 is that well voltages can go below zero volts, and thus might forward bias a substrate diode (not shown) formed between the PFETs MP 1 , MP 2 , MP 3 and MP 4 and a substrate on which they are formed.
  • the NFETs MN 1 , MN 2 , MN 3 , MN 4 , MN 5 , and MN 6 are preferably placed either in a deep trench or a deep n-well since the substrate on which they are formed is connected to a fixed voltage node such as ground.
  • FIG. 7 depicts a deep trench negative metal oxide semiconductor (NMOS) device structure 90 that is suitable for implementing the NMOS devices depicted in FIG. 6 .
  • the NMOS device structure includes a source (S), a gate (G), and a drain (D).
  • a bulk or body (B) connection is also included that can be connected to a fixed voltage node to control a body effect, which if left uncontrolled may result in degradations of many specified parameters of the NMOS device structure 90 .
  • a deep trench 92 is highly oxidized to provide insulation between a substrate 94 and an N-Well 96 .
  • the substrate 94 is highly conductive and is preferably connected to a fixed voltage node such as ground GND.
  • FIG. 8 depicts a deep trench positive metal oxide semiconductor (PMOS) device structure 98 that is suitable for implementing the PMOS devices depicted in FIG. 6 .
  • the PMOS device structure 98 includes a source (S), a gate (G), and a drain (D).
  • a bulk or body (B) connection is also included that can be connected to a fixed voltage node to control the body effect, which if left uncontrolled may result in degradations of many specified parameters of the PMOS device structure 98 .
  • the PMOS device structure 98 is contained within a deep trench 100 that is highly oxidized to provide insulation between a general substrate 102 and a P-Well 104 that serves as a substrate for the PMOS device structure 98 .
  • the substrate 102 is highly conductive and is connected to a fixed voltage node such as ground GND.
  • FIG. 9 depicts a deep N-Well NMOS device structure 106 that is suitable for implementing the NMOS devices depicted in FIG. 6 .
  • the deep N-Well NMOS device structure 106 provides isolation from a substrate 108 and hence substrate noise while also allowing a voltage other than V dd and ground by placing a source (S), a gate (G) and a drain (D) of the deep N-Well NMOS device structure 106 within a P-Well 110 .
  • a deep N-Well section 112 is typically connected to the highest voltage available, which is usually V dd .
  • a bulk or body (B) connection is also included that can be connected to a fixed voltage node to control a body effect, which if left uncontrolled may result in degradations of many specified parameters of the deep N-Well NMOS device structure 106 .
  • FIG. 10 is a graph depicting output voltage measurements for a realized circuit based upon the high efficiency regulated negative charge-pump 78 depicted in FIG. 6 .
  • a positive output voltage curve that includes the point (Ay, Ax) shows that a positive regulated voltage V dd reaches a steady state voltage of 5.3V in around 6 ⁇ S after the high efficiency regulated negative charge-pump 78 is activated.
  • a negative output voltage curve that includes a point (Bx, By) for the output voltage V OUT reaches a steady state voltage of ⁇ 5.2V in around 8 ⁇ S after the high efficiency regulated negative charge-pump 78 is activated.
  • FIG. 11 depicts the basic architecture of user equipment (UE) in the form of a mobile terminal 114 that incorporates an embodiment of the high efficiency regulated negative charge-pump 78 ( FIG. 6 ).
  • the high efficiency regulated negative charge-pump 78 is usable to activate a multi-band duplexer or radio frequency (RF) switch 116 in the mobile terminal 114 .
  • the mobile terminal 114 may include a receiver front end 118 , a radio frequency (RF) transmitter section 120 , an antenna 122 , a baseband processor 124 , a control system 126 , a frequency synthesizer 128 , and an interface 130 .
  • the receiver front end 118 receives information bearing radio frequency signals from one or more remote transmitters provided by a base station (not shown).
  • a low noise amplifier (LNA) 132 amplifies the signal.
  • a filter circuit 134 minimizes broadband interference in the received signal, while down conversion and digitization circuitry 136 down converts the filtered, received signal to an intermediate or baseband frequency signal, which is then digitized into one or more digital streams.
  • the receiver front end 118 typically uses one or more mixing frequencies generated by the frequency synthesizer 128 .
  • the baseband processor 124 processes the digitized received signal to extract the information or data bits conveyed in the received signal. This processing typically comprises demodulation, decoding, and error correction operations. As such, the baseband processor 124 is generally implemented in one or more digital signal processors (DSPs).
  • DSPs digital signal processors
  • the baseband processor 124 receives digitized data, which may represent voice, data, or control information, from the control system 126 , which it encodes for transmission.
  • the encoded data is output to the RF transmitter section 120 , where it is used by a modulator 138 to modulate a carrier signal that is at a desired transmit frequency.
  • a power amplifier circuitry 140 amplifies the modulated carrier signal to a level appropriate for transmission, and delivers the amplified and modulated carrier signal to the antenna 122 through the duplexer or RF switch 116 .
  • the control system 126 controls an ENABLE signal that activates and deactivates the high efficiency regulated negative charge-pump 78 as needed.
  • control system 126 may activate the high efficiency regulated negative charge-pump 78 in anticipation of closing a MEMS switch (not shown) or other device for a transmission event. Alternately, the control system 126 may deactivate the high efficiency regulated negative charge-pump 78 to conserve energy.
  • a user may interact with the mobile terminal 114 via the interface 130 , which may include interface circuitry 142 associated with a microphone 144 , a speaker 146 , a keypad 148 , and a display 150 .
  • the interface circuitry 142 typically includes analog-to-digital converters, digital-to-analog converters, amplifiers, and the like. Additionally, it may include a voice encoder/decoder, in which case it may communicate directly with the baseband processor 124 .
  • the microphone 144 will typically convert audio input, such as the user's voice, into an electrical signal, which is then digitized and passed directly or indirectly to the baseband processor 124 .
  • Audio information encoded in the received signal is recovered by the baseband processor 124 , and converted by the interface circuitry 142 into an analog signal suitable for driving the speaker 146 .
  • the keypad 148 and the display 150 enable the user to interact with the mobile terminal 114 , input numbers to be dialed, address book information, or the like, as well as monitor call progress information.

Abstract

A charge-pump circuit for providing a regulated negative voltage is disclosed. The charge-pump circuit includes at least one flying capacitor stage having a capacitor with a first terminal selectively coupled between a negative voltage input through a first electronic switch and a negative voltage output through a second electronic switch. A second terminal of the capacitor is selectively coupled between a fixed voltage node through a third electronic switch and an error signal input through a fourth electronic switch. A positive voltage source is coupled to the negative voltage output through a feedback network. A feedback amplifier having an error signal output, a reference voltage input, and a feedback input is coupled to the feedback network. A switch controller having a first clock output drives the first electronic switch and the third electronic switch, while a second clock output drives the second electronic switch and the fourth electronic switch.

Description

    RELATED APPLICATION
  • This application claims the benefit of provisional patent application Ser. No. 61/446,171, filed Feb. 24, 2011, the disclosure of which is hereby incorporated herein by reference in its entirety.
    • FIELD OF THE DISCLOSURE
  • The present disclosure relates to charge-pumps that provide regulated negative voltages.
    • BACKGROUND
  • Traditionally, negative voltage charge-pumps are used to control radio frequency (RF) switches that are implemented using a pseudomorphic high electron mobility transistor/complementary metal oxide semiconductor (pHEMT/CMOS) process. Negative voltage generated by a negative voltage charge-pump is usable to turn off pHEMT/CMOS based RF switches. Using a negative voltage instead of a positive voltage improves the isolation of a pHEMT/CMOS based RF switch and eliminates the need for DC blocking capacitors for proper operation of pHEMT/CMOS based RF switches. The lack of blocking capacitors reduces the area needed to implement a pHEMT/CMOS based RF switch, which simplifies the design of electrostatic discharge (ESD) protection.
  • RF switches driven by a negative charge-pump typically have leakage currents that are supplied through a negative voltage output of the negative charge-pump. If an unregulated negative charge-pump is used to supply the leakage currents, an output voltage provided at the negative voltage output drops as the leakage currents increase. As a result, insertion losses and isolation numbers for the RF switches are adversely affected. In contrast, a regulated negative charge-pump will maintain a fixed output voltage as the leakage currents increase. It has been recognized that improved efficiencies can be realized by sourcing load currents in a feedback loop of the regulated negative charge-pump directly from a main power supply. For example, twice as much current will be drained from the main power supply if a load current is sourced from a voltage doubled section of the feedback loop. Such a large drain of current from the main power supply is inefficient and undesirable.
  • A regulated negative charge-pump will operate most efficiently when voltage regulation of the output voltage of the regulated negative charge-pump is maintained near to the regulated negative charge-pump's ideal output voltage. For example, an ideal output voltage for a regulated negative charge-pump that doubles a source voltage is twice the voltage of the source voltage. In general, a regulated negative charge-pump that is designed to boost a source voltage Vdd by a multiplication factor N will operate most efficiently when a negative output voltage VOUT is maintained at N times the source voltage Vdd. Efficiency for a charge-pump is given by the following equation:

  • Efficiency=V OUT/(N*V dd)
  • However, achieving a maximum efficiency depends on a given design specification and in some cases it might not be possible to regulate the negative output voltage VOUT close to an ideal voltage because the ideal voltage might be in the breakdown region of a CMOS switch being driven by the negative output voltage VOUT.
  • One way to implement a regulated negative charge-pump is through the use of a shunt regulator at the output of an unregulated negative charge-pump. FIG. 1 depicts a related art shunt regulated negative charge-pump 10 having a flying capacitor stage 12 with a capacitor CFLY having a first terminal that is selectively coupled between a first negative voltage source 14 through a first electronic switch 51 and a negative voltage output 16 through a second electronic switch S2. The capacitor CFLY also has a second terminal that is coupled to a fixed voltage node such as ground GND. The first electronic switch S1 is driven by a clock signal CLK, and the second electronic switch S2 is driven by a clock signal CLK. The clock signals CLK and CLK are non-overlapping and out of phase relative to each other. A positive regulated voltage source 18 is communicatively coupled to the negative voltage output 16 through a feedback network 20 made up of a first resistor R1 and a second resistor R2 coupled in a voltage divider configuration. An error amplifier 22 has an inverting input 24 coupled to a voltage divider node 26 between the first resistor R1 and the second resistor R2. The error amplifier 22 further includes a non-inverting input 28 that is coupled to a negative voltage reference −VREF.
  • The error amplifier 22 is powered by a second negative voltage source 32 that provides a negative supply voltage that is above the negative output voltage VOUT, and a third negative voltage source 34 that provides a negative voltage that is below the negative output voltage VOUT. A voltage of −3Vdd for the first negative voltage source 14 and the third negative voltage source 34 is generated by a negative voltage quadrupler (not shown). A voltage of −2Vdd for the second negative voltage source 32 is generated by a negative voltage tripler (not shown). The negative voltage tripler is able to triple the source voltage Vdd because a voltage equal to −Vdd is generated by a voltage doubler circuit (not shown) that is sourced from Vdd. Alternately, a cascading of two voltage doubler circuits can be adapted to provide a voltage tripler circuit.
  • The shunt regulated negative charge-pump 10 also includes an n-channel enhancement mode FET M1 that has a gate coupled to an error signal output 30 of the error amplifier 22. The FET M1 also has a source coupled to the third negative voltage source 34, and a drain coupled to the negative voltage output 16. A load capacitor CLOAD has a first terminal coupled to the negative voltage output 16, and a second terminal coupled to a fixed voltage node such as ground GND.
  • When the switch S1 is closed and the switch S2 is open, the flying capacitor CFLY is charged to −3Vdd. When the switch S2 is closed and the switch S1 is open, the FET M1 turns on and pulls charge away from the capacitor CFLY and the capacitor CLOAD until a voltage at the voltage divider node 26 is equal to the reference voltage −VREF. The load current ILOAD comes from the second negative voltage source 32, which in this case supplies a voltage of −2Vdd. As a result of the second negative voltage source 32 supplying the load current ILOAD at a voltage of −2Vdd, the source of the voltage Vdd must supply three times as much current as the load current ILOAD. Thus, the efficiency of the shunt regulated negative charge-pump 10 is less than the efficiency desired for battery powered equipment such as mobile terminals.
  • Another way to implement a regulated negative charge-pump is to use a series regulator at the output of an unregulated negative charge-pump. FIG. 2 depicts a related art series regulated negative charge-pump 36 that is similar to the shunt regulated negative charge-pump 10 (FIG. 1). However, in this particular case, the FET M1 is a p-channel enhancement mode type device that has a drain coupled directly to the second negative voltage source 32. In contrast to the shunt regulated charge-pump 10, the FET M1 has a source coupled to the negative voltage output 16. The source of the FET M1 is also coupled to the third negative voltage source 34 through a third resistor R3. However, even with these structural changes that implement series regulation in place of shunt regulation, the problem of inefficient operation remains. In effect, the load current ILOAD is still supplied by the second negative voltage source 32, which in this case supplies a voltage of −2Vdd. As a result of the second negative voltage source 32 supplying the load current ILOAD at a voltage of −2Vdd, the source of the voltage Vdd must supply three times as much current as the load current ILOAD. Thus, the series regulated negative charge-pump 36 also provides less than the efficiency desired for battery powered equipment such as mobile terminals. Therefore, a need remains for a high efficiency regulated negative charge-pump.
    • SUMMARY
  • The present disclosure provides a high efficiency negative regulated charge-pump, which in certain embodiments is implemented via a Silicon-on-insulator (SOI) process or a Deep negative-well (N-Well) complementary metal oxide semiconductor (CMOS) process. In particular, the present disclosure provides a circuit that includes at least one flying capacitor stage with a capacitor having a first terminal that is selectively coupled to either a negative voltage input through a first electronic switch or a negative voltage output through a second electronic switch. The capacitor also has a second terminal that is selectively coupled between a fixed voltage node through a third electronic switch and an error signal input through a fourth electronic switch. The circuit also has a positive voltage source that is communicably coupled to the negative voltage output through a feedback network having a feedback output. Also included in the circuit is a feedback amplifier having an error signal output, a reference voltage input, and a feedback input coupled to the feedback output of the feedback network. The error signal output of the feedback amplifier is coupled to the error signal input. Moreover, a switch controller has a first clock output for driving the first electronic switch and the third electronic switch, and a second clock output for driving the second electronic switch and the fourth electronic switch.
  • Those skilled in the art will appreciate the scope of the present disclosure and realize additional aspects thereof after reading the following detailed description of the preferred embodiments in association with the accompanying drawing figures.
    • BRIEF DESCRIPTION OF THE DRAWING FIGURES
  • The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure.
  • FIG. 1 depicts a related art shunt regulated negative charge-pump.
  • FIG. 2 depicts a related art series regulated negative charge-pump.
  • FIG. 3 depicts a high efficiency regulated negative charge-pump that is in accordance with the present disclosure.
  • FIG. 4 depicts a regulated negative charge-pump that is driven by a negative voltage doubler having two stages in accordance with the present disclosure.
  • FIG. 5 depicts a regulated negative charge-pump having a plurality of stages that are driven by a feedback amplifier that is in accordance with the present disclosure.
  • FIG. 6 depicts a detailed circuit implementation of the high efficiency regulated negative charge-pump of the present disclosure.
  • FIG. 7 depicts a deep trench negative metal oxide semiconductor (NMOS) device structure that is suitable for implementing the NMOS devices depicted in FIG. 6.
  • FIG. 8 depicts a deep trench positive metal oxide semiconductor (PMOS) device structure that is suitable for implementing the PMOS devices depicted in FIG. 6.
  • FIG. 9 depicts a deep N-Well NMOS structure that is suitable for implementing the NMOS devices depicted in FIG. 6.
  • FIG. 10 is a graph depicting output voltage measurements for a realized circuit based upon the circuit depicted in FIG. 6.
  • FIG. 11 depicts user equipment (UE) in the form of a mobile terminal that incorporates a preferred embodiment of the circuit of FIG. 6.
    •  DETAILED DESCRIPTION
  • The embodiments set forth below represent the necessary information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure and the accompanying claims.
  • FIG. 3 depicts a high efficiency regulated negative charge-pump 38 that is in accordance with the present disclosure. The high efficiency regulated negative charge-pump 38 includes a flying capacitor stage 40 with a capacitor CFLY having a first terminal that is selectively coupled to either a negative voltage source 42 through a first electronic switch S1 or a negative voltage output 44 through a second electronic switch S2. The capacitor CFLY also has a second terminal that is selectively coupled to a fixed voltage node such as ground GND through a third electronic switch S3. The second terminal of the capacitor CFLY is also selectively coupled through a fourth electronic switch S4 to an error signal input 48. A positive voltage source 50 is communicably coupled to the negative voltage output 44 through a feedback network 52 made up of a first resistor R1 and a second resistor R2 coupled in a voltage divider configuration. A feedback amplifier 54 has an inverting input 56 coupled to a feedback output at a voltage divider node 58 between the first resistor R1 and the second resistor R2. The feedback amplifier 54 also includes a non-inverting input 60 that is coupled to a positive voltage reference +VREF.
  • The feedback amplifier 54 further includes an output 62 that is coupled to the error signal input 48. Unlike the regulated negative charge-pump 10 (FIG. 1) and the regulated negative charge-pump 36 (FIG. 2), the feedback amplifier 54 may be powered directly from Vdd and a fixed voltage node, which in this case is ground GND. Therefore, a load current ILOAD is directly supplied from Vdd. As a result of ILOAD being directly supplied by Vdd, the high efficiency regulated negative charge-pump 38 is at least three times as efficient as either the regulated negative charge-pump 10 or the regulated negative charge-pump 36.
  • In operation, the electronic switches S1 and S3 are closed in response to a first state of the first clock signal CLK, while the switches S2 and S4 are opened in response to a first state of the second clock signal CLK. While the electronic switches S1 and S3 are closed, the capacitor CFLY is charged to a voltage level of −3Vdd. Once the capacitor CFLY is charged, the electronic switches S1 and S3 are opened in response to a second state of the first clock signal CLK. After a short delay that prevents an overlap of the first clock signal CLK and the second clock signal CLK, the electronic switches S2 and S4 are closed in response to a second state of the second clock signal CLK. At this point, the output 62 of the feedback amplifier 54 provides an output voltage level that adds or subtracts from the voltage of the charged capacitor CFLY depending upon a comparison of the reference voltage +VREF and the feedback output at a voltage level present at the voltage divider node 58. For example, if the voltage level present at the voltage divider node 58 is greater than the reference voltage +VREF, the output 62 will pull charges from the capacitor CFLY and the capacitor CLOAD. Alternately, if the voltage level present at the voltage divider node 58 is less than the reference voltage +VREF, the output 62 will add charge to the capacitor CFLY and the capacitor CLOAD. In this way, a negative voltage level IOUT provided at the negative voltage output 44 is regulated.
  • FIG. 4 depicts another regulated negative charge-pump 64 that is in accordance with the present disclosure. The regulated negative charge-pump 64 has a first stage 66 and a second stage 68 that are driven by a negative voltage doubler circuit 70. The first stage 66 includes a flying capacitor CFLY1 having a first terminal coupled to a first electronic switch S11 and a second electronic switch S21. The flying capacitor CFLY1 also has a second terminal coupled to a third electronic switch S31 and a fourth electronic switch S41. The second stage 68 includes a flying capacitor CFLY2 having a first terminal coupled to a first electronic switch S12 and a second electronic switch S22. The flying capacitor CFLY2 also has a second terminal coupled to a third electronic switch S32 and a fourth electronic switch S42.
  • The first terminal of the flying capacitor CFLY1 is selectively coupled to the negative voltage doubler 70 via the first electronic switch S11, while the second terminal of the flying capacitor CFLY2 is selectively coupled to a fixed voltage node such as ground GND. The first terminal of the flying capacitor CFLY1 is also selectively coupled to the first terminal of the flying capacitor CFLY2 via the second electronic switch S21 of the first stage 66 and the first electronic switch S12 of the second stage 68, wherein the first electronic switch S12 and the second electronic switch S21 are both driven by the second clock signal CLK. The first terminal of the flying capacitor CFLY2 is also selectively coupled to the negative voltage output 44 through the second electronic switch S22. The second terminal of the flying capacitor CFLY2 is selectively coupled to the second terminal of the flying capacitor CFLY1 via the third electronic switch S32 and the third electronic switch S41. The second terminal of the flying capacitor CFLY2 is selectively coupled to the output 62 of the feedback amplifier 54 through the fourth electronic switch S42.
  • In operation, the electronic switches S11 and S31 are closed in response to a first state of the first clock signal CLK, while the electronic switches S21, S41, S12, and S32 are opened in response to a first state of the second clock signal CLK. While the electronic switches S11 and S31 are closed, the capacitor CFLY1 is charged to a voltage level of around −3Vdd. Once the capacitor CFLY1 is charged, the electronic switches S11 and S31 are opened in response to a second state of the first clock signal CLK. After a short delay that prevents an overlap of the first clock signal CLK and the second clock signal CLK, the electronic switches S21, S41, S12 and S32 are closed in response to a second state of the second clock signal CLK.
  • At this point, the output 62 of the feedback amplifier 54 provides an output voltage level that adds or subtracts from the voltage of the capacitors CFLY1 and CFLY2 depending upon a comparison of the reference voltage +VREF and the feedback output at a voltage level present at the voltage divider node 58. For example, if the voltage level present at the voltage divider node 58 is greater than the reference voltage +VREF, the output 62 will pull charge from the capacitors CFLY1 and CFLY2. Alternately, if the voltage level present at the voltage divider node 58 is less than the reference voltage +VREF, the output 62 will add charge to the capacitors CFLY1 and CFLY2.
  • Next, the first clock signal CLK and the second clock signal CLKboth change state so that the electronic switches 521, 541, S12 and S32 are opened, while the electronic switches S11, 531, S22 and S42 are closed. As such, the charge is transferred from the capacitor CFLY2 to the capacitor CLOAD, while the feedback amplifier 54 provides an output voltage level that adds or subtracts from the voltage of the capacitors CFLY1 and CFLY2 depending upon a comparison of the reference voltage +VREF and the feedback output at a voltage level present at the voltage divider node 58. In this way, a negative voltage level VOUT, provided at the negative voltage output 44, is regulated. Also note that the capacitor CFLY1 is being recharged as charge is being transferred from CFLY2 to CLOAD.
  • FIG. 5 depicts a regulated negative charge-pump 72 that extends the two stage embodiment of the regulated negative charge pump 64 (FIG. 4) to include additional flying capacitor stages in accordance with the present disclosure. In this embodiment, (N+1) stages are added to the first stage 66, where (N+1) is a total number of flying capacitor stages included in the regulated negative charge-pump 72. Instead of selectively coupling the first terminal of the first flying capacitor CFLY1 with a negative voltage source, the first terminal of the first flying capacitor CFLY1 is selectively coupled to a fixed voltage node such as ground GND through the first first-stage electronic switch S11. Moreover, instead of selectively coupling the second terminal of the first flying capacitor CFLY1 to ground GND, the second terminal is selectively coupled to the voltage source Vdd, through the fourth first-stage electronic switch S41.
  • A stage N 74 includes a flying capacitor CFLYN having a first terminal coupled to a first electronic switch S4N and a second electronic switch S2N. The flying capacitor CFLYN also has a second terminal coupled to a third electronic switch S3N and a fourth electronic switch S4N. The first terminal of CFLYN is selectively coupled to a previous stage through the first electronic switch S1N. For example, if the total number of stages (N+1) equals three, then the first electronic switch S1N will be coupled to the electronic switch S21 of the first stage 66. A second terminal of the flying capacitor CFLYN is selectively coupled to the output 62 of the feedback amplifier 54 through the third electronic switch S3N.
  • A stage (N+1) 76 includes a flying capacitor CFLY(N+1) having a first terminal coupled to a first electronic switch S1(N+1) and a second electronic switch S2(N+1). The flying capacitor CFLY(N+1) also has a second terminal coupled to a third electronic switch S3(N+1) and a fourth electronic switch S4(N+1). The first terminal of the flying capacitor CFLY(N+1) is selectively coupled to a first terminal of the flying capacitor CFLYN of the stage N via the first electronic switch S1(N+1) and the second electronic switch S2N that are both driven by the first clock signal CLK. The first terminal of the flying capacitor CFLY(N+1) is also selectively coupled to the negative voltage output 44 through the second electronic switch S2(N+1). The second terminal of the flying capacitor CFLY(N+1) is selectively coupled to the second terminal of the flying capacitor CFLYN via the third electronic switch S3(N+1) and the third switch S3N. The second terminal of the flying capacitor CFLY(N+1) is selectively coupled to the output 62 of the feedback amplifier 54 through the fourth electronic switch S4(N+1).
  • FIG. 6 depicts a detailed circuit implementation of a high efficiency regulated negative charge-pump 78 in accordance with the present disclosure. A cross-coupled negative charge pump circuit 80 having a first P-FET MP1, a second P-FET MP2, a first N-FET MN1 and a second N-FET MN2 along with a first flying capacitor CF1, a second flying capacitor CF2 and a first load capacitor CL1 provides the high efficiency regulated negative charge-pump 78 with an input voltage of −Vdd. A first terminal of the first flying capacitor CF1 is driven by a first clock signal CLK, and a first terminal of the second flying capacitor CF2 is driven by a second clock signal CLK. The first clock signal CLK is opposite in phase to the second clock signal CLK, and in this case the amplitude of the first clock signal CLK and the amplitude of the second clock signal CLK are both about equal to Vdd. A switch controller 79 has a first clock output for providing the first clock signal CLK and a second clock output for providing the second clock signal CLK. Although the switch controller 79 is depicted as an element of the regulated negative charge-pump 78, the switch controller 79 could also be external of the regulated negative charge-pump 78.
  • The high efficiency regulated negative charge-pump 78 includes a P-FET MP3, a P-FET MP4, an N-FET MN3, an NFET MN4, an NFET MN5 and an NFET MN6. The high efficiency regulated negative charge-pump 78 also includes flying capacitors CF3, CF4, CF5 and CF6. A load capacitor CLOAD is coupled between a negative voltage output 81 and a fixed voltage node such as ground GND. A first terminal of the flying capacitor CF3 is selectively coupled to the negative voltage output 81 through a first electronic switch SW1 that is responsive to the second clock signal CLK. A second terminal of the flying capacitor CF3 is selectively coupled to ground GND through the NFET MN5 having a gate that is responsive to the first clock signal CLK. A first terminal of the flying capacitor CF6 is selectively coupled to the negative voltage output 81 through a second electronic switch SW2 that is responsive to the first clock signal CLK. A second terminal of the flying capacitor CF6 is selectively coupled to ground GND through the NFET MN6 having a gate that is responsive to the second clock signal CLK. The sources of PFET MP3 and the PFET MP4 receive the −Vdd voltage provided by the cross-coupled negative charge pump circuit 80. The flying capacitor CF4 is coupled between a drain of the PFET MP3 and a gate of the NFET MN6, which is driven by the second clock signal CLK. The flying capacitor CF5 is coupled between a drain of the PFET MP4 and a gate of the NFET MN5, which is driven by the first clock signal CLK.
  • The NFET MN3 has a source coupled to a first terminal of the flying capacitor CF3 that is coupled to the first electronic switch SW1. A drain of the NFET MN3 is coupled to a first terminal of the flying capacitor CF4 and to a drain of the PFET MP3. A gate of the NFET MN3 is coupled to the gate of PFET MP3, which in turn is coupled to the drain of the PFET MP4 and the source of NFET MN4. In a symmetrical configuration, the NFET MN4 has a source coupled to a first terminal of the flying capacitor CF5 that is coupled to the second electronic switch SW2. A gate of the NFET MN4 is coupled to the gate of PFET MP4, which in turn is coupled to the drain of the PFET MP3 and the source of the NFET MN3.
  • A second terminal of the capacitor CF4 is driven by the second clock signal CLK, which has an amplitude that alternates between around zero volts and around Vdd. Similarly, the second terminal of the capacitor CF5 is driven by the first clock signal CLK, which has an amplitude that alternates between around Vdd and around zero volts.
  • Regulation of a negative output voltage VOUT at the negative voltage output 81 is maintained by a feedback amplifier 82 that has a non-inverting input 84 coupled to a positive voltage reference +VREF and an inverting input 86 coupled to a voltage feedback signal VFB that is a sample of the negative output voltage. An output terminal 88 of the feedback amplifier 82 is selectively coupled to the second terminal of the flying capacitor CF3 through an electronic switch SW3 that is driven by the second clock signal CLK. Another electronic switch SW4 that is driven by the first clock signal CLK selectively couples an output voltage provided at the output terminal 88 of the feedback amplifier 82 to the second terminal of the flying capacitor CF6.
  • In operation, during a first charging phase when the first clock signal CLK is around +Vdd and the second clock signal CLK is around zero volts, the flying capacitor CF4 is charged to −Vdd. As the second clock signal CLKtransitions to an amplitude of around +Vdd, the voltage across CF4 is raised to around −2Vdd. During a first output regulation phase, as the first clock signal CLK transitions to around +Vdd and the second clock signal CLKtransitions low, the electronic switch SW3 closes in response to the second clock signal CLK. As a result, an output voltage provided at the output terminal 88 adjusts the voltage across the flying capacitor CF3. If the voltage level of the feedback signal VFB is less than the voltage level of the positive reference voltage +VREF, the output voltage provided at the output terminal 88 will add charge to the flying capacitor CF3. Alternately, if the voltage level of the feedback signal VFB is greater than the voltage level of the positive reference voltage +VREF, the output voltage provided at the output terminal 88 will subtract charge from the flying capacitor CF3.
  • During a second charging phase when the first clock signal CLK is around zero volts and the second clock signal CLK is around +Vdd, the flying capacitor CF6 is charged to −Vdd. As the first clock signal CLK transitions to an amplitude of around +Vdd, the voltage across CF6 is raised to around −2Vdd. During a second output regulation phase, the first clock signal CLK transitions to around zero volts and the second clock signal CLKtransitions to around zero volts, the electronic switch SW4 closes in response to the first clock signal CLK.
  • As a result, an output voltage provided at the output terminal 88 adjusts the voltage across the flying capacitor CF6. If the voltage level of the feedback signal VFB is less than the voltage level of the positive reference voltage +VREF, the output voltage provided at the output terminal 88 will add charge to the flying capacitor CF6. Alternately, if the voltage level of the feedback signal VFB is greater than the voltage level of the positive reference voltage +VREF, the output voltage provided at the output terminal 88 will subtract charge from the flying capacitor CF6.
  • Note that the high efficiency regulated negative charge pump 78 can be converted to a high efficiency regulated positive charge pump by replacing the PMOS transistors with NMOS transistors and vice versa. The negative voltage reference −VREF should also be replaced by a positive voltage reference +VREF.
  • The high efficiency regulated negative charge pump 78 is preferably fabricated such that the PFETs MP1, MP2, MP3 and MP4 are placed in a deep trench using an SOI process. The reason for placing the PFETs MP1, MP2, MP3 and MP4 is that well voltages can go below zero volts, and thus might forward bias a substrate diode (not shown) formed between the PFETs MP1, MP2, MP3 and MP4 and a substrate on which they are formed. Similarly, the NFETs MN1, MN2, MN3, MN4, MN5, and MN6 are preferably placed either in a deep trench or a deep n-well since the substrate on which they are formed is connected to a fixed voltage node such as ground.
  • FIG. 7 depicts a deep trench negative metal oxide semiconductor (NMOS) device structure 90 that is suitable for implementing the NMOS devices depicted in FIG. 6. The NMOS device structure includes a source (S), a gate (G), and a drain (D). A bulk or body (B) connection is also included that can be connected to a fixed voltage node to control a body effect, which if left uncontrolled may result in degradations of many specified parameters of the NMOS device structure 90. In particular, a deep trench 92 is highly oxidized to provide insulation between a substrate 94 and an N-Well 96. In contrast to the deep trench 92, the substrate 94 is highly conductive and is preferably connected to a fixed voltage node such as ground GND.
  • FIG. 8 depicts a deep trench positive metal oxide semiconductor (PMOS) device structure 98 that is suitable for implementing the PMOS devices depicted in FIG. 6. The PMOS device structure 98 includes a source (S), a gate (G), and a drain (D). A bulk or body (B) connection is also included that can be connected to a fixed voltage node to control the body effect, which if left uncontrolled may result in degradations of many specified parameters of the PMOS device structure 98. The PMOS device structure 98 is contained within a deep trench 100 that is highly oxidized to provide insulation between a general substrate 102 and a P-Well 104 that serves as a substrate for the PMOS device structure 98. In contrast, the substrate 102 is highly conductive and is connected to a fixed voltage node such as ground GND.
  • FIG. 9 depicts a deep N-Well NMOS device structure 106 that is suitable for implementing the NMOS devices depicted in FIG. 6. The deep N-Well NMOS device structure 106 provides isolation from a substrate 108 and hence substrate noise while also allowing a voltage other than Vdd and ground by placing a source (S), a gate (G) and a drain (D) of the deep N-Well NMOS device structure 106 within a P-Well 110. A deep N-Well section 112 is typically connected to the highest voltage available, which is usually Vdd. A bulk or body (B) connection is also included that can be connected to a fixed voltage node to control a body effect, which if left uncontrolled may result in degradations of many specified parameters of the deep N-Well NMOS device structure 106.
  • FIG. 10 is a graph depicting output voltage measurements for a realized circuit based upon the high efficiency regulated negative charge-pump 78 depicted in FIG. 6. A positive output voltage curve that includes the point (Ay, Ax) shows that a positive regulated voltage Vdd reaches a steady state voltage of 5.3V in around 6 μS after the high efficiency regulated negative charge-pump 78 is activated. A negative output voltage curve that includes a point (Bx, By) for the output voltage VOUT reaches a steady state voltage of −5.2V in around 8 μS after the high efficiency regulated negative charge-pump 78 is activated.
  • FIG. 11 depicts the basic architecture of user equipment (UE) in the form of a mobile terminal 114 that incorporates an embodiment of the high efficiency regulated negative charge-pump 78 (FIG. 6). In particular, the high efficiency regulated negative charge-pump 78 is usable to activate a multi-band duplexer or radio frequency (RF) switch 116 in the mobile terminal 114. The mobile terminal 114 may include a receiver front end 118, a radio frequency (RF) transmitter section 120, an antenna 122, a baseband processor 124, a control system 126, a frequency synthesizer 128, and an interface 130. The receiver front end 118 receives information bearing radio frequency signals from one or more remote transmitters provided by a base station (not shown). A low noise amplifier (LNA) 132 amplifies the signal. A filter circuit 134 minimizes broadband interference in the received signal, while down conversion and digitization circuitry 136 down converts the filtered, received signal to an intermediate or baseband frequency signal, which is then digitized into one or more digital streams. The receiver front end 118 typically uses one or more mixing frequencies generated by the frequency synthesizer 128. The baseband processor 124 processes the digitized received signal to extract the information or data bits conveyed in the received signal. This processing typically comprises demodulation, decoding, and error correction operations. As such, the baseband processor 124 is generally implemented in one or more digital signal processors (DSPs).
  • On the transmit side, the baseband processor 124 receives digitized data, which may represent voice, data, or control information, from the control system 126, which it encodes for transmission. The encoded data is output to the RF transmitter section 120, where it is used by a modulator 138 to modulate a carrier signal that is at a desired transmit frequency. A power amplifier circuitry 140 amplifies the modulated carrier signal to a level appropriate for transmission, and delivers the amplified and modulated carrier signal to the antenna 122 through the duplexer or RF switch 116. The control system 126 controls an ENABLE signal that activates and deactivates the high efficiency regulated negative charge-pump 78 as needed. For example, the control system 126 may activate the high efficiency regulated negative charge-pump 78 in anticipation of closing a MEMS switch (not shown) or other device for a transmission event. Alternately, the control system 126 may deactivate the high efficiency regulated negative charge-pump 78 to conserve energy.
  • A user may interact with the mobile terminal 114 via the interface 130, which may include interface circuitry 142 associated with a microphone 144, a speaker 146, a keypad 148, and a display 150. The interface circuitry 142 typically includes analog-to-digital converters, digital-to-analog converters, amplifiers, and the like. Additionally, it may include a voice encoder/decoder, in which case it may communicate directly with the baseband processor 124. The microphone 144 will typically convert audio input, such as the user's voice, into an electrical signal, which is then digitized and passed directly or indirectly to the baseband processor 124. Audio information encoded in the received signal is recovered by the baseband processor 124, and converted by the interface circuitry 142 into an analog signal suitable for driving the speaker 146. The keypad 148 and the display 150 enable the user to interact with the mobile terminal 114, input numbers to be dialed, address book information, or the like, as well as monitor call progress information.
  • Those skilled in the art will recognize improvements and modifications to the preferred embodiments of the present disclosure. All such improvements and modifications are considered within the scope of the concepts disclosed herein and the claims that follow.

Claims (20)

1. A charge-pump circuit comprising:
at least one flying capacitor stage with a capacitor having a first terminal that is selectively coupled between one of a negative voltage input through a first electronic switch and a negative voltage output through a second electronic switch, the capacitor having a second terminal that is selectively coupled between one of a fixed voltage node through a third electronic switch and an error signal input through a fourth electronic switch;
a positive voltage source communicably coupled to the negative voltage output through a feedback network having a feedback output;
a feedback amplifier having an error signal output coupled to the error signal input, a reference voltage input, and a feedback input coupled to the feedback output of the feedback network; and
a switch controller having a first clock output for driving the first electronic switch and the third electronic switch, and a second clock output for driving the second electronic switch and the fourth electronic switch.
2. The charge-pump circuit of claim 1, wherein a first clock signal that is output from the first clock output is substantially inverse in phase to a second clock signal that is output from the second clock output.
3. The charge-pump circuit of claim 2, wherein the first clock signal and the second clock signal are substantially non-overlapping.
4. The charge-pump circuit of claim 1, wherein the fixed voltage node is ground.
5. The charge-pump circuit of claim 1, wherein the feedback amplifier is powered by a positive voltage source.
6. The charge-pump circuit of claim 1, wherein the feedback network is a first resistor and a second resistor coupled in a voltage divider configuration.
7. The charge-pump circuit of claim 6, wherein the feedback output is coupled to and between the first resistor and the second resistor.
8. The charge-pump circuit of claim 1, wherein the reference voltage input is adapted to receive a positive band gap voltage reference.
9. The charge-pump circuit of claim 1, wherein the charge-pump circuit is implemented via a Silicon-on-insulator (SOI) process.
10. The charge-pump circuit of claim 1, wherein the charge-pump circuit is implemented via a Deep negative-well (N-Well) complementary metal oxide semiconductor (CMOS) process.
11. A mobile terminal comprising:
an antenna;
a radio frequency (RF) switch coupled to the antenna;
a charge-pump circuit for activating the RF switch, the charge pump circuit comprising:
at least one flying capacitor stage with a capacitor having a first terminal that is selectively coupled between one of a negative voltage input through a first electronic switch and a negative voltage output through a second electronic switch, the capacitor having a second terminal that is selectively coupled between one of a fixed voltage node through a third electronic switch and an error signal input through a fourth electronic switch;
a positive voltage source communicably coupled to the negative voltage output through a feedback network having a feedback output;
a feedback amplifier having an error signal output coupled to the error signal input, a reference voltage input, and a feedback input coupled to the feedback output of the feedback network; and
a switch controller having a first clock output for driving the first electronic switch and the third electronic switch, and a second clock output for driving the second electronic switch and the fourth electronic switch; and
a control system for enabling and disabling the charge-pump circuit.
12. The mobile terminal of claim 11, wherein a first clock signal that is output from the first clock output is substantially inverse in phase to a second clock signal that is output from the second clock output.
13. The mobile terminal of claim 12, wherein the first clock signal and the second clock signal are substantially non-overlapping.
14. The mobile terminal of claim 11, wherein the fixed voltage node is ground.
15. The mobile terminal of claim 11, wherein the feedback amplifier is powered by a positive voltage source.
16. The mobile terminal of claim 11, wherein the feedback network is a first resistor and a second resistor coupled in a voltage divider configuration.
17. The mobile terminal of claim 16, wherein the feedback output is coupled to and between the first resistor and the second resistor.
18. The mobile terminal of claim 11, wherein the reference voltage input is adapted to receive a positive band gap voltage reference.
19. The mobile terminal of claim 11, wherein the charge-pump circuit is implemented via a Silicon-on-insulator (SOI) process.
20. The mobile terminal of claim 11, wherein the charge-pump circuit is implemented via a Deep negative-well (N-Well) complementary metal oxide semiconductor (CMOS) process.
US13/105,012 2011-02-24 2011-05-11 High efficiency negative regulated charge-pump Expired - Fee Related US8461910B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US13/105,012 US8461910B2 (en) 2011-02-24 2011-05-11 High efficiency negative regulated charge-pump

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201161446171P 2011-02-24 2011-02-24
US13/105,012 US8461910B2 (en) 2011-02-24 2011-05-11 High efficiency negative regulated charge-pump

Publications (2)

Publication Number Publication Date
US20120218032A1 true US20120218032A1 (en) 2012-08-30
US8461910B2 US8461910B2 (en) 2013-06-11

Family

ID=46718567

Family Applications (1)

Application Number Title Priority Date Filing Date
US13/105,012 Expired - Fee Related US8461910B2 (en) 2011-02-24 2011-05-11 High efficiency negative regulated charge-pump

Country Status (1)

Country Link
US (1) US8461910B2 (en)

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120274393A1 (en) * 2011-04-01 2012-11-01 Stmicroelectronics S.R.I. Dynamic biasing circuit for a protection stage using low voltage transistors
US20130162336A1 (en) * 2007-08-08 2013-06-27 Advanced Analogic Technologies, Inc. Time-Multiplexed-Capacitor DC/DC Converter With Multiple Outputs
US9071055B2 (en) 2006-10-21 2015-06-30 Advanced Analogic Technologies Incorporated Charging scheme
WO2015115783A1 (en) * 2014-02-03 2015-08-06 Samsung Electronics Co., Ltd. Charging circuit and electronic device having the same
CN105356742A (en) * 2015-11-06 2016-02-24 灿芯半导体(上海)有限公司 High-efficiency charge pump
US9285821B2 (en) 2014-06-05 2016-03-15 Powerchip Technology Corporation Negative reference voltage generating circuit and negative reference voltage generating system using the same
CN105576964A (en) * 2014-10-30 2016-05-11 联发科技（新加坡）私人有限公司 Charge pump circuit, integrated circuit, electronic device and method therefor
CN105576963A (en) * 2014-10-30 2016-05-11 联发科技（新加坡）私人有限公司 Charge pump circuit, integrated circuit, electronic device and method therefor
US9397562B1 (en) 2015-01-13 2016-07-19 Powerchip Technology Corporation Negative reference voltage generating circuit and system thereof
US9502969B2 (en) 2015-01-19 2016-11-22 Powerchip Technology Corporation Negative reference voltage generating circuit
US20180159523A1 (en) * 2016-12-06 2018-06-07 Analog Devices Global Charge injection compensation circuit
KR20180136649A (en) * 2017-06-15 2018-12-26 한국과학기술원 Step-Up/Step-Down DC-DC converter using flying capacitor and control method threror
CN111510825A (en) * 2015-01-19 2020-08-07 德州仪器公司 Duty cycle microphone/transducer for acoustic analysis
US20220085808A1 (en) * 2017-02-13 2022-03-17 Skyworks Solutions, Inc. Voltage generators with charge pumps for switch circuits
US11329554B2 (en) * 2018-05-17 2022-05-10 Ams Ag Charge pump circuit arrangement
WO2023038190A1 (en) * 2021-09-13 2023-03-16 주식회사 엠디엠 Initial charge converter
US20230077529A1 (en) * 2021-09-10 2023-03-16 Egalax_Empia Technology Inc. Voltage doubler switched capacitor circuit capable of detecting short circuit of flying capacitor and detection method thereof
US11694632B2 (en) * 2020-04-28 2023-07-04 Samsung Display Co., Ltd. Power voltage generator including charge pump, display apparatus including the same and method of generating power voltage using the same

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101712070B1 (en) * 2010-05-06 2017-03-06 삼성디스플레이 주식회사 Voltage generating circuit and display device having the same
CN104518663B (en) * 2014-07-18 2017-03-29 上海华虹宏力半导体制造有限公司 Negative pressure charge pump feedback circuit
US9729048B2 (en) 2014-08-04 2017-08-08 Skyworks Solutions, Inc. Apparatus and methods for charge pumps for radio frequency systems
US9602921B2 (en) 2015-06-24 2017-03-21 Robert Bosch Gmbh Independently charge pumps for differential microphone
KR102426494B1 (en) 2015-07-07 2022-07-27 삼성전자주식회사 Charge pump and devices having the same
US9621033B2 (en) 2015-09-09 2017-04-11 Nxp Usa, Inc. Charge pump circuit for providing multiplied voltage
US10333393B2 (en) * 2016-09-23 2019-06-25 Qualcomm Incorporated Embedded charge pump voltage regulator
US10749429B2 (en) 2017-02-28 2020-08-18 Linear Technology Llc Methods and systems of reducing charge pump substrate noise
TWI641229B (en) * 2018-02-26 2018-11-11 國立交通大學 Charge pump circuit and phase locked loop system

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6400211B1 (en) * 2000-09-19 2002-06-04 Rohm Co., Ltd. DC/DC converter
US20080122941A1 (en) * 2006-11-29 2008-05-29 Sony Corporation Solid-state imaging device and imaging apparatus
US7535281B2 (en) * 2006-09-29 2009-05-19 Micron Technology, Inc. Reduced time constant charge pump and method for charging a capacitive load
US7990741B2 (en) * 2008-07-16 2011-08-02 Aptina Imaging Corporation Comparator controlled charge pump for negative voltage booster

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5680300A (en) 1995-12-22 1997-10-21 Analog Devices, Inc. Regulated charge pump DC/DC converter
DE69733603D1 (en) 1997-01-23 2005-07-28 St Microelectronics Srl NMOS, negative charge pump
US6300820B1 (en) 2000-02-07 2001-10-09 Exar Corporation Voltage regulated charge pump
US6522558B2 (en) 2000-06-13 2003-02-18 Linfinity Microelectronics Single mode buck/boost regulating charge pump
US6452438B1 (en) 2000-12-28 2002-09-17 Intel Corporation Triple well no body effect negative charge pump

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6400211B1 (en) * 2000-09-19 2002-06-04 Rohm Co., Ltd. DC/DC converter
US7535281B2 (en) * 2006-09-29 2009-05-19 Micron Technology, Inc. Reduced time constant charge pump and method for charging a capacitive load
US20080122941A1 (en) * 2006-11-29 2008-05-29 Sony Corporation Solid-state imaging device and imaging apparatus
US7990741B2 (en) * 2008-07-16 2011-08-02 Aptina Imaging Corporation Comparator controlled charge pump for negative voltage booster

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9071055B2 (en) 2006-10-21 2015-06-30 Advanced Analogic Technologies Incorporated Charging scheme
US20130162336A1 (en) * 2007-08-08 2013-06-27 Advanced Analogic Technologies, Inc. Time-Multiplexed-Capacitor DC/DC Converter With Multiple Outputs
US8841891B2 (en) * 2007-08-08 2014-09-23 Advanced Analogic Technologies Incorporated Time-multiplexed-capacitor DC/DC converter with multiple outputs
US9225239B2 (en) 2007-08-08 2015-12-29 Advanced Analogic Technologies, Incorporated Multiple output charge pump with multiple flying capacitors
US8604868B2 (en) * 2011-04-01 2013-12-10 Stmicroelectronics S.R.L. Dynamic biasing circuit for a protection stage using low voltage transistors
US20120274393A1 (en) * 2011-04-01 2012-11-01 Stmicroelectronics S.R.I. Dynamic biasing circuit for a protection stage using low voltage transistors
US10135274B2 (en) 2014-02-03 2018-11-20 Samsung Electronics Co., Ltd. Charging circuit and electronic device having the same
WO2015115783A1 (en) * 2014-02-03 2015-08-06 Samsung Electronics Co., Ltd. Charging circuit and electronic device having the same
US9285821B2 (en) 2014-06-05 2016-03-15 Powerchip Technology Corporation Negative reference voltage generating circuit and negative reference voltage generating system using the same
CN105576964A (en) * 2014-10-30 2016-05-11 联发科技（新加坡）私人有限公司 Charge pump circuit, integrated circuit, electronic device and method therefor
CN105576963A (en) * 2014-10-30 2016-05-11 联发科技（新加坡）私人有限公司 Charge pump circuit, integrated circuit, electronic device and method therefor
US9837892B2 (en) 2014-10-30 2017-12-05 Mediatek Singapore Pte. Ltd. Charge pump circuit, integrated circuit, electronic device and method therefor
US9397562B1 (en) 2015-01-13 2016-07-19 Powerchip Technology Corporation Negative reference voltage generating circuit and system thereof
US9502969B2 (en) 2015-01-19 2016-11-22 Powerchip Technology Corporation Negative reference voltage generating circuit
CN111510825A (en) * 2015-01-19 2020-08-07 德州仪器公司 Duty cycle microphone/transducer for acoustic analysis
CN105356742A (en) * 2015-11-06 2016-02-24 灿芯半导体(上海)有限公司 High-efficiency charge pump
US20180159523A1 (en) * 2016-12-06 2018-06-07 Analog Devices Global Charge injection compensation circuit
US10277223B2 (en) * 2016-12-06 2019-04-30 Analog Devices Global Charge injection compensation circuit
CN108155896A (en) * 2016-12-06 2018-06-12 亚德诺半导体集团 Charge injecting compensating circuit
US20220085808A1 (en) * 2017-02-13 2022-03-17 Skyworks Solutions, Inc. Voltage generators with charge pumps for switch circuits
US11689202B2 (en) * 2017-02-13 2023-06-27 Skyworks Solutions, Inc. Voltage generators with charge pumps for switch circuits
KR20180136649A (en) * 2017-06-15 2018-12-26 한국과학기술원 Step-Up/Step-Down DC-DC converter using flying capacitor and control method threror
KR101987238B1 (en) 2017-06-15 2019-06-11 한국과학기술원 Step-Up/Step-Down DC-DC converter using flying capacitor and control method threror
US11329554B2 (en) * 2018-05-17 2022-05-10 Ams Ag Charge pump circuit arrangement
US11694632B2 (en) * 2020-04-28 2023-07-04 Samsung Display Co., Ltd. Power voltage generator including charge pump, display apparatus including the same and method of generating power voltage using the same
US20230077529A1 (en) * 2021-09-10 2023-03-16 Egalax_Empia Technology Inc. Voltage doubler switched capacitor circuit capable of detecting short circuit of flying capacitor and detection method thereof
US11870344B2 (en) * 2021-09-10 2024-01-09 Egalax Empia Technology Inc. Voltage doubler switched capacitor circuit capable of detecting short circuit of flying capacitor and detection method thereof
WO2023038190A1 (en) * 2021-09-13 2023-03-16 주식회사 엠디엠 Initial charge converter

Also Published As

Publication number Publication date
US8461910B2 (en) 2013-06-11

Similar Documents

Publication Publication Date Title
US8461910B2 (en) High efficiency negative regulated charge-pump
US9225234B2 (en) In-rush current control for charge-pump LDO
JP5156774B2 (en) Charge pump device and output power generation method
US7336056B1 (en) Switching power converter that supports both a boost mode of operation and a buck mode of operation using a common duty-cycle timing signal
US7586295B2 (en) Voltage up-conversion circuit
US9111601B2 (en) Negative voltage generators
US8130042B2 (en) Methods and devices for leakage current reduction
US11251708B2 (en) Inverting switching regulator using charge pump and operating method thereof
US9236957B2 (en) Technique to reduce the third harmonic of an on-state RF switch
US9148052B2 (en) Switching regulator with reduced EMI
US9515555B2 (en) Floating power converter having multiple voltage inputs
TW200913468A (en) Amplifier with configurable DC-coupled or AC-coupled output
US7285940B2 (en) Voltage regulator with shunt feedback
US7741912B1 (en) Varying amplifier bias parameters to meet radio frequency (RF) communications requirements
US9244478B2 (en) Local voltage control for isolated transistor arrays
US7805170B2 (en) System and method for efficient power supply regulation compatible with radio frequency operation
JP2013532458A (en) High voltage inversion type charge pump
EP2899885B1 (en) A low power level-shift circuit for data dependent signals
US7482864B1 (en) Method and system for FET-based amplifier circuits
US9331655B2 (en) Pop-click noise grounding switch design with deep sub-micron CMOS technology
US9411387B2 (en) Pre-charging mechanism for multi-input switching charger
CN112688712A (en) Radio frequency device and voltage generating device thereof
US7579920B1 (en) Self-biasing low-phase noise LC oscillator

Legal Events

Date Code Title Description
AS Assignment

Owner name: RF MICRO DEVICES, INC., NORTH CAROLINA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:NADIMPALLI, PRAVEEN VARMA;REEL/FRAME:026257/0332

Effective date: 20110510

AS Assignment

Owner name: BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT, TE

Free format text: NOTICE OF GRANT OF SECURITY INTEREST IN PATENTS;ASSIGNOR:RF MICRO DEVICES, INC.;REEL/FRAME:030045/0831

Effective date: 20130319

AS Assignment

Owner name: RF MICRO DEVICES, INC., NORTH CAROLINA

Free format text: TERMINATION AND RELEASE OF SECURITY INTEREST IN PATENTS (RECORDED 3/19/13 AT REEL/FRAME 030045/0831);ASSIGNOR:BANK OF AMERICA, N.A., AS ADMINISTRATIVE AGENT;REEL/FRAME:035334/0363

Effective date: 20150326

AS Assignment

Owner name: QORVO US, INC., NORTH CAROLINA

Free format text: MERGER;ASSIGNOR:RF MICRO DEVICES, INC.;REEL/FRAME:039196/0941

Effective date: 20160330

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Expired due to failure to pay maintenance fee

Effective date: 20170611